package com.mj.controller.common;

import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.lang3.StringUtils;
import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;
import com.mj.util.MD5Util;

/**
 * 生成二维码
 *
 */
public class QRUtil {
	private static final int WHITE = 0xFFFFFFFF;
	private static final int BLACK = 0xFF000000;
	private static final String UPLOAD = "upload";

	/**
	 * 静态生成二维码 存储在磁盘上
	 * 
	 * @param content
	 *            //二维码信息
	 * @param contextPath
	 *            //上下文相对路径
	 * @param realPath
	 *            //磁盘真实路径
	 * @param subPath
	 *            //子路径
	 * @return
	 */
	@SuppressWarnings({ "rawtypes", "unchecked" })
	public static String generateQrcode(String content, String contextPath, String realPath, String subPath) {
		if (content == null || realPath == null)
			return null;
		String fileName = generateFileName(content.getBytes()) + ".png";
		String url = "/" + UPLOAD + contextPath + "/" + subPath + "/" + fileName;// 图片在项目中存储的相对路径
		String filePath = url;
		// 如果是部署在服务器上的情况，则需要到webapps/下面的upload目录
		if (StringUtils.isNotBlank(contextPath) || realPath.endsWith("root")) {
			filePath = ".." + url;
		}
		MultiFormatWriter multiFormatWriter = new MultiFormatWriter();
		Map hints = new HashMap();
		hints.put(EncodeHintType.CHARACTER_SET, "UTF-8"); // 设置字符集编码类型
		BitMatrix bitMatrix = null;
		try {
			bitMatrix = multiFormatWriter.encode(content, BarcodeFormat.QR_CODE, 300, 300, hints);
			File file1 = new File(realPath, filePath); // 创建存储图片的文件
			try {
				QRUtil.writeToFile(bitMatrix, "png", file1); // 存储二维码图片
				return filePath;
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		} catch (WriterException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		}
		return null;
	}

	private static void writeToFile(BitMatrix matrix, String format, File file) throws IOException {
		BufferedImage image = toBufferedImage(matrix);
		if (!ImageIO.write(image, format, file)) {
			throw new IOException("Could not write an image of format " + format + " to " + file);
		}
	}

	private static BufferedImage toBufferedImage(BitMatrix matrix) {
		int width = matrix.getWidth();
		int height = matrix.getHeight();
		BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
		for (int x = 0; x < width; x++) {
			for (int y = 0; y < height; y++) {
				image.setRGB(x, y, matrix.get(x, y) ? BLACK : WHITE);
			}
		}
		return image;
	}

	private static String generateFileName(byte[] content) {
		return MD5Util.getMD5String(content); // md5加密
	}

	/**
	 * 生成二维码图片 不存储 直接以流的形式输出到页面
	 * 
	 * @param content
	 * @param response
	 */
	@SuppressWarnings({ "unchecked", "rawtypes" })
	public static void encodeQrcode(String content, HttpServletResponse response) {
		if (StringUtils.isBlank(content))
			return;
		MultiFormatWriter multiFormatWriter = new MultiFormatWriter();
		Map hints = new HashMap();
		hints.put(EncodeHintType.CHARACTER_SET, "UTF-8"); // 设置字符集编码类型
		BitMatrix bitMatrix = null;
		try {
			bitMatrix = multiFormatWriter.encode(content, BarcodeFormat.QR_CODE, 300, 300, hints);
			BufferedImage image = toBufferedImage(bitMatrix);
			// 输出二维码图片流
			try {
				ImageIO.write(image, "png", response.getOutputStream());
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		} catch (WriterException e1) {
			// TODO Auto-generated catch block
			e1.printStackTrace();
		}
	}
}